But the parks bureau says it cannot complete the trail project without tearing down at least one tree, and this proposal will save dozens of other trees. The 120-foot-tall tree will be repurposed as part of the city's first nature play area in Westmoreland Park.

The Greenway Trail project will build a 10.4-mile trail in North Portland, connecting Kelley Point Park to the Eastbank Esplanade. The bureau held an open house in December 2011 and presented plans then, Ross said, to install a bridge there.

"Planning this project meant that we have had to balance a lot of desires, regulations (and) the way the topography/land is laid out ..." Parks spokesman Mark Ross wrote on the bureau's Facebook page. "The plan as it stands has the least impact to trees while accommodating all other requirements. That means if we didn't pursue the current plan, we would have had to consider an option that required removing a cluster of trees, instead of just one. ... If there was way of doing the project that didn't involve removing this tree, we would have certainly pursued it."

But residents urged the bureau to continue to look for solutions that would not involve removing a tree. Neighbors have tied notes and photographs around the 18-foot-in-diameter tree.

"It is unbelievable that Portland Parks cannot find a way to circumvent this beautiful, treasured, healthy, tree," wrote Greg Snider. "What is the Parks Department for if not for coming up with creative solutions to not only save our dwindling canopy, but also to protect the few remaining significant, elder trees?"

To mitigate the loss of the tree, the parks bureau will plant seven giant sequoias in neighboring Chimney Park, along with four douglas firs, four western red cedars and two dozen other trees. The felled tree will go to Westmoreland as logs and benches for the new nature park.

The bureau must cut down this tree before March 1 to avoid issues with migratory birds, Ross said. Otherwise, birds would begin nesting in the tree, and the bureau would have to wait until after nesting season.